Here is the JSONB-related code in my Tenant model. In both cases, storing values as JSONB allows saving any kind of data without having to mess with migrations, so you have the best of both worlds. In an app with multiple tenants, it’s often the case that each tenant wants some kind of customisation, and the ‘tenants’ table would need to have columns for each and every setting requested by any number of tenants. In a single-tenant situation, it would not make much sense to add/rename columns on a table which never holds more than one record. ![]() This method generates accessor and change-tracking methods, so that data stored in a JSON/JSONB column is as easy to work with as regular columns.Īs with everything, you’ll need to weigh the pros and cons before deciding to use dedicated columns or dumping everything as JSONB, but here’s a situation where I find JSONB is appropriate: tenant settings. This allows validations and callbacks to work seamlessly with JSON data for instance. It takes a column name, keys, and allows prefixing or suffixing the generated accessors. The store_accessor class method is defined in ActiveRecord::Store::ClassMethods module, which is automatically included with ActiveRecord. I highly recommend Nando Vieira’s blog post Using PostgreSQL and jsonb with Ruby on Rails if you want to read more about database performance and how to query using attributes stored inside JSONB columns. It’s important to note that the JSONB format allows indexing and searching, and is not much slower than plain JSON, so you’re better off using JSONB everywhere. In this article, we will cover in detail how to utilize both views and materialized views within Ruby on Rails, and we can even take a look at creating and modifying them with database migrations. You can store native JSON data in PostgreSQL databases version 9.4+, and ActiveRecord allows taking advantage of that format. Luckily Postgres provides two ways to encapsulate large queries: Views and Materialized Views. If you’re using ActiveModel Serializers, postgres_ext-serializers is a way to still leverage the underlying database.You can store native JSON data in Postgres databases, and Rails now allows taking advantage of that format. If your schema follows JSON:API specifications, fast_jsonapi might be useful. If your codebase includes critical paths where JSON generation is involved, consider leveraging the database for serialization. While some of the processing time was shifted to ActiveRecord, the overall query duration becomes significantly faster. The positive impact on query speeds is clear:Ĭompleted 200 OK in 41ms (Views: 0.1ms | ActiveRecord: 33.6ms | Allocations: 2206) first || "" end def users render json: query_to_json ( User. ![]() new ( cte_table, cte_definition ) json = Arel :: SelectManager. new ( query_sql ) cte = Arel :: Nodes :: As. new ( :orig_query ) cte_definition = Arel :: Nodes :: Grouping. # More efficient replacement for ResultSet#to_json def query_to_json ( query ) query_sql = Arel. The SQL for the expression looks something like array_to_json(array_agg(original_query)). In this code snippet we’re creating a helper method query_to_json, which will transform the given query into a Postgres has a wide variety of JSON functions we can use to construct JSON. That way we’re shifting majority of the work onto more optimized database workers. Instead of returning each row from the database query, we can augment the database query to aggregate all results into the JSON What if we could just skip the Ruby processing? Solution Large number of heap allocations and CPU time spent on doing the transformation. Ruby’s dynamic nature results into relatively The query, and then converting each object one by one to the JSON representation. JSON Serialization in Rails is slow, because the JSON transformation ResultSet#to_json involves first allocating a Rails object for each row returned from It’s not terrible, but the time spent rendering the view and the number of allocations seems strangely high. Here’s how the response looks like in the Rails console:Ĭompleted 200 OK in 91ms (Views: 61.9ms | ActiveRecord: 22.5ms | Allocations: 25990) ![]() ![]() Like the endpoint is slower than it should be even in the local development environment where latency is zero and there is no user load.
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